After hydrocarbons have been removed from the ground, the fluid stream (e.g., crude oil, natural gas) is transported from place-to-place via pipelines. It is desirable to know with accuracy the amount of fluid flowing a pipeline, and particular accuracy is demanded when the fluid is changing hands, or “custody transfer.” Ultrasonic flow meters may be used to measure the amount of fluid flowing in a pipeline, and ultrasonic flow meters have sufficient accuracy to be used in custody transfer. The value of gas “changing hands” at the point of custody transfer in a high volume natural gas pipeline may amount to a million dollars or more in a single day. For this reason, manufacturers attempt to make ultrasonic meters that are not only very accurate, but also reliable in the sense that the mean time between failures is large.
Thus, any advance which increases the reliability of ultrasonic meters, and/or which decreases the time to troubleshoot and repair time after an ultrasonic meter has failed, would provide a competitive advantage in the marketplace.